piece with a hole in it appears to be a cover that is part of the trans bell housing looks like it may be a separate piece that can be replaced easily yes looking at the photo it almost looks like something came out of the cover to make that hole kinda like an alien chestburster if this is correct then i would be looking in there for possibly missing parts like bolts tranny pump pieces or flex plate pieces if not then maybe you just hit something while driving to cause the hole